.top {
  padding: 5px 10px;
  line-height: 50px;
  text-align: center;
  border-radius: 5px;
  cursor: pointer;
  background-color: rgb(9, 121, 165);
  color: #fff;
  position: fixed;
  bottom: 30px;
  right: 30px;
  transition: all .5s;
  border: 1px solid #000;
  z-index: 9999;
  /* 不让选择文字 */
  -webkit-user-select: none;
  -moz-user-select: none;
  -ms-user-select: none;
  user-select: none;
}